using EAIAdminDAL.DTO;
using GB5Shared.DTO.Framework.Login;
using GB5Shared.ExternalAI;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.Logging;
using System;
using System.Net.Http;
using System.Text.Json;
using System.Threading;
using System.Threading.Tasks;

namespace EAIAdminBLL.Sync
{
    /// <summary>
    /// EAIAdmin's concrete IEAISyncClient — resolves its own AIEngineOptions from the
    /// "EAIAdmin:AIExtract" config section directly (not via generic IOptions&lt;AIEngineOptions&gt;
    /// DI, which would collide with KMS's own "KMS:AIExtract" binding of the same options TYPE
    /// inside one PlatformHost process — see GB5Shared.ExternalAI.AIEngineOptions's own doc
    /// comment). Built on top of the shared, assembly-scan-registered IAIEngineSyncClient
    /// transport.
    /// </summary>
    public class EAISyncClient : IEAISyncClient
    {
        private const string SectionName = "EAIAdmin:AIExtract";

        private readonly IAIEngineSyncClient _transport;
        private readonly AIEngineOptions _options;
        private readonly ILogger<EAISyncClient> _logger;

        public EAISyncClient(
            IAIEngineSyncClient transport,
            IConfiguration configuration,
            ILogger<EAISyncClient> logger)
        {
            _transport = transport ?? throw new ArgumentNullException(nameof(transport));
            _logger    = logger    ?? throw new ArgumentNullException(nameof(logger));

            _options = configuration.GetSection(SectionName).Get<AIEngineOptions>() ?? new AIEngineOptions();
            if (string.IsNullOrWhiteSpace(_options.SigningKeyVaultPath))
                _options.SigningKeyVaultPath = "eaiadmin/ai-enterprise-jwt-secret";
            if (string.IsNullOrWhiteSpace(_options.Issuer))
                _options.Issuer = "GB5-EAIAdmin";
        }

        // ── Initiative ──────────────────────────────────────────────────────────────

        public Task<EAISyncResult> PushInitiativeAsync(
            EAIInitiativeAdminDTO dto, LoginDTO login, CancellationToken ct = default)
            => PushAsync("/api/admin/initiative", "InitiativeCode", dto.InitiativeCode, new
            {
                initiativeCode = dto.InitiativeCode,
                initiativeName = dto.InitiativeName,
                maturityLevel  = dto.MaturityLevel
            }, "aiInitiativeId", login, ct);

        public Task<EAISyncResult> DeleteInitiativeAsync(
            EAIInitiativeAdminDTO dto, LoginDTO login, CancellationToken ct = default)
            => DeleteAsync("/api/admin/initiative", dto.EAIRemoteId, dto.InitiativeCode, login, ct);

        // ── Capability ──────────────────────────────────────────────────────────────

        public Task<EAISyncResult> PushCapabilityAsync(
            EAICapabilityAdminDTO dto, LoginDTO login, CancellationToken ct = default)
            => PushAsync("/api/admin/capability", "CapabilityCode", dto.CapabilityCode, new
            {
                capabilityCode   = dto.CapabilityCode,
                capabilityName   = dto.CapabilityName,
                maxMaturityLevel = dto.MaxMaturityLevel,
                keywords         = dto.Keywords
            }, "aiCapabilityId", login, ct);

        public Task<EAISyncResult> DeleteCapabilityAsync(
            EAICapabilityAdminDTO dto, LoginDTO login, CancellationToken ct = default)
            => DeleteAsync("/api/admin/capability", dto.EAIRemoteId, dto.CapabilityCode, login, ct);

        // ── Bot ─────────────────────────────────────────────────────────────────────

        public Task<EAISyncResult> PushBotAsync(
            EAIBotAdminDTO dto, LoginDTO login, CancellationToken ct = default)
            => PushAsync("/api/admin/bot", "BotCode", dto.BotCode, new
            {
                botCode        = dto.BotCode,
                name           = dto.Name,
                initiativeCode = dto.InitiativeCode,
                description    = dto.Description,
                isReadOnly     = dto.IsReadOnly
            }, "aiBotId", login, ct);

        public Task<EAISyncResult> DeleteBotAsync(
            EAIBotAdminDTO dto, LoginDTO login, CancellationToken ct = default)
            => DeleteAsync("/api/admin/bot", dto.EAIRemoteId, dto.BotCode, login, ct);

        // ── PromptTemplate ──────────────────────────────────────────────────────────

        public async Task<EAISyncResult> PushPromptTemplateAsync(
            EAIPromptTemplateAdminDTO dto, LoginDTO login, CancellationToken ct = default)
        {
            var body = new
            {
                tenantId       = login.ClientId,
                initiativeCode = dto.InitiativeCode,
                capabilityCode = dto.CapabilityCode,
                promptTemplate = dto.PromptTemplate,
                variantCode    = dto.VariantCode
            };

            // Extends the existing PUT /api/admin/prompt (gbEAI Part 1 change: becomes a proper
            // upsert, gains a GET/DELETE sibling) rather than a new admin_* router — this is the
            // one entity gbEAI already had a partial admin route for.
            var response = await _transport.SendJsonAsync(
                _options, HttpMethod.Put, "/api/admin/prompt", body, login, ct).ConfigureAwait(false);

            if (!response.IsSuccess)
            {
                _logger.LogWarning(
                    "EAISyncClient | PushPromptTemplate | Failed | {Initiative}/{Capability} | {Error}",
                    dto.InitiativeCode, dto.CapabilityCode, response.ErrorMessage);
                return new EAISyncResult { Success = false, Message = response.ErrorMessage };
            }

            return new EAISyncResult
            {
                Success       = true,
                EAIRemoteId   = TryGetLong(response.Body, "aiPromptId"),
                PromptVersion = (int?)TryGetLong(response.Body, "version")
            };
        }

        public Task<EAISyncResult> DeletePromptTemplateAsync(
            EAIPromptTemplateAdminDTO dto, LoginDTO login, CancellationToken ct = default)
            => DeleteAsync("/api/admin/prompt", dto.EAIRemoteId,
                $"{dto.InitiativeCode}/{dto.CapabilityCode}", login, ct);

        // ── ModelConfig ─────────────────────────────────────────────────────────────

        public async Task<EAISyncResult> PushModelConfigAsync(
            EAIModelConfigAdminDTO dto, LoginDTO login, CancellationToken ct = default)
        {
            // Deliberately never sends a raw key — gbEAI has no Vault client of its own; the
            // secret stays GB5-side only, resolved at outbound-call time by whichever module
            // ends up calling the model (out of scope for this admin-config push).
            var body = new
            {
                tenantId  = login.ClientId,
                modelCode = dto.ModelCode,
                modelName = dto.ModelName,
                provider  = dto.Provider,
                endpoint  = dto.Endpoint
            };

            var response = await _transport.SendJsonAsync(
                _options, HttpMethod.Put, "/api/admin/model", body, login, ct).ConfigureAwait(false);

            if (!response.IsSuccess)
            {
                _logger.LogWarning(
                    "EAISyncClient | PushModelConfig | Failed | ModelCode={Code} | {Error}",
                    dto.ModelCode, response.ErrorMessage);
                return new EAISyncResult { Success = false, Message = response.ErrorMessage };
            }

            return new EAISyncResult { Success = true, EAIRemoteId = TryGetLong(response.Body, "aiModelId") };
        }

        public Task<EAISyncResult> DeleteModelConfigAsync(
            EAIModelConfigAdminDTO dto, LoginDTO login, CancellationToken ct = default)
            => DeleteAsync("/api/admin/model", dto.EAIRemoteId, dto.ModelCode, login, ct);

        // ── AgentRoute ──────────────────────────────────────────────────────────────

        public Task<EAISyncResult> PushAgentRouteAsync(
            EAIAgentRouteAdminDTO dto, LoginDTO login, CancellationToken ct = default)
            => PushAsync("/api/admin/agentroute", "Slug", dto.Slug, new
            {
                slug              = dto.Slug,
                initiativeCode    = dto.InitiativeCode,
                defaultCapability = dto.DefaultCapability,
                module            = dto.Module,
                summary           = dto.Summary,
                capabilities      = dto.Capabilities,
                aliases           = dto.Aliases,
                acceptsFile       = dto.AcceptsFile,
                acceptsText       = dto.AcceptsText,
                requiresFile      = dto.RequiresFile
            }, "agentRouteId", login, ct);

        public Task<EAISyncResult> DeleteAgentRouteAsync(
            EAIAgentRouteAdminDTO dto, LoginDTO login, CancellationToken ct = default)
            => DeleteAsync("/api/admin/agentroute", dto.EAIRemoteId, dto.Slug, login, ct);

        // ── Shared plumbing ─────────────────────────────────────────────────────────

        private async Task<EAISyncResult> PushAsync(
            string path, string codeFieldName, string codeValue, object body,
            string remoteIdJsonProperty, LoginDTO login, CancellationToken ct)
        {
            var response = await _transport.SendJsonAsync(
                _options, HttpMethod.Post, path, body, login, ct).ConfigureAwait(false);

            if (!response.IsSuccess)
            {
                _logger.LogWarning(
                    "EAISyncClient | Push | Failed | Path={Path} | {CodeField}={CodeValue} | {Error}",
                    path, codeFieldName, codeValue, response.ErrorMessage);
                return new EAISyncResult { Success = false, Message = response.ErrorMessage };
            }

            return new EAISyncResult { Success = true, EAIRemoteId = TryGetLong(response.Body, remoteIdJsonProperty) };
        }

        private async Task<EAISyncResult> DeleteAsync(
            string path, long? remoteId, string identifierForLog, LoginDTO login, CancellationToken ct)
        {
            if (remoteId is not { } id)
                return EAISyncResult.Skipped("Never synced to AI-Enterprise-v1.0 — nothing to delete remotely.");

            var response = await _transport.SendJsonAsync(
                _options, HttpMethod.Delete, $"{path}/{id}", null, login, ct).ConfigureAwait(false);

            if (!response.IsSuccess)
            {
                _logger.LogWarning(
                    "EAISyncClient | Delete | Failed | Path={Path} | {Identifier} | {Error}",
                    path, identifierForLog, response.ErrorMessage);
                return new EAISyncResult { Success = false, Message = response.ErrorMessage };
            }

            return new EAISyncResult { Success = true };
        }

        private static long? TryGetLong(string json, string propertyName)
        {
            if (string.IsNullOrWhiteSpace(json)) return null;

            try
            {
                using var doc = JsonDocument.Parse(json);
                if (doc.RootElement.ValueKind == JsonValueKind.Object
                    && doc.RootElement.TryGetProperty(propertyName, out var el)
                    && el.ValueKind == JsonValueKind.Number)
                {
                    return el.GetInt64();
                }
            }
            catch (JsonException)
            {
                // Not the expected shape — leave the field unset rather than throw; the local
                // save already succeeded and remains authoritative.
            }

            return null;
        }
    }
}